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<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>JS set</title>
</head>
<body>
<p>forEach() 方法为每个 Set 元素调用函数</p>
<p id="demo"></p>
<script>
  const letters = new Set(["a","b","c"]);

  let text = "";
  letters.forEach(function (value){
    text += value + "<br/>";
  })

  document.getElementById("demo").innerHTML = text;
</script>
</body>
</html>